JPS63142345A - High image forming composition containing azinium activating agent - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention This invention relates to photography, and more particularly, this invention relates to novel imageable compositions and novel coatings containing these imageable compositions. Regarding.

[Prior art]

A variety of photographic imaging systems are known in which curable organic components containing ethylenically unsaturated sites (s i to) are used for imaging. The organic component undergoes a photoinduced addition reaction, typically either polymerization or crosslinking, at the ethylenically unsaturated sites that causes curing and achieves image identification.

Coinitiators (coini-
tiator) is the -i method.

One of the coinitiators is a photosensitizer. A photosensitizer is considered to capture photons of exposing radiation (or radiation, hereinafter the same). The remaining co-initiator is called an activator (or activator, hereinafter the same). The activator is not directly sensitive to exposing radiation, but the adjacent activating molecules react with the photosensitizer molecule, exciting the latter by photon capture, followed by the release of free radicals by the activator. , triggers an immobilizing addition reaction at the ethylenically unsaturated site.

It is generally accepted that photosensitizer co-initiators act to lift electrons from occupied molecular orbitals to higher energy unoccupied orbitals by photon absorption. The spin of an electron lifted into a higher energy orbit corresponds to the spin it exhibits in its initial orbit or ground state.

Thus, the photosensitizer in its initially formed excited state is in an excited state. - The duration of the excited state is typically limited to less than 2.3 nanoseconds. The excited photosensitizer returns directly from its excited state to its initial ground state and can dissipate the captured photon energy. In addition, in some cases, the excited state of the fluorescent agent is
Intersystem crossing to another excited state, called a triple state, through spin inversion
ng), and in the triple state the lifetime is typically in the microsecond to millisecond range. A photosensitizer coinitiator that exhibits a triple state remains in the excited state for a time that is an order of magnitude greater than a photosensitizer coinitiator that exhibits only an excited state, so that the paired activator A longer period of time is available for reaction with co-initiator.

5 pecht and Farid British publication tube 2.0
No. 83,832A discloses a photopolymerization coinitiator containing an azinium activator and an amino-substituted 3-ketocoumarin, and a naphthothiazole merocyanine photosensitizer coinitiator that exhibits a triple state upon excitation. Most photosensitizers, which absorb primarily in the ultraviolet part of the spectrum, consist of yellow dyes with absorption maxima in the wavelength range up to 480 ne. The essentially cumulative disclosure is Re5e
arch Disclosure, Vol, 200+D
ec.

1980, Item 20036. R
e5earchDisclosure is Kennet
h Mason Publications, Ltd.

Emsworth, Hampshire POIO7D
Published by D, England. 5 pecht
, Martic, and Farid, “A NewC
lass of Triplet 5ensitize
rs”, Tetrahedron.

Vol, 38. pp, 1203-1211.1982
These amino-substituted 3-ketocoumarins exhibit intersystem cross-over efficiencies of greater than 10%, such as in the range of 0.18-0.92 or 18-92%, as shown in .

5 pecht and Parid, in a comparative example, demonstrate the performance of ethyl diethylaminobenzoate as an activator in place of the disclosed N-oxyazinium activator. The results show that ethyldiethylaminobenzoate exhibits relatively lower speed with amino-substituted coumarins compared to oxy-substituted coumarins.

[Purpose of the invention]

The object of the present invention is to provide an organic component containing ethylenically unsaturated sites and capable of being selectively cured by addition at the ethylenically unsaturated sites, an azinium salt activator, and a reduction potential of the azinium salt activator. enhanced imaging capabili
The object is to provide a composition having at least +0.2 volts true on the electron-donating amino group and the benzene ring in the imageable composition described above. Image enhancer substituted with one or more groups capable of imparting Hammett sigma electron withdrawing
of benzene.

Negative-acting imageable compositions that undergo curing by addition reactions at sites of ethylenically unsaturation incorporate certain enhancers that act as azinium activators, photosensitizers, and co-initiators. It has been found that its performance can be improved by

The sensitivity of the imageable compositions of the present invention is determined by the presence of the azinium activator and photosensitizer together with the third enhancing co-initiator - specifically, the true It is a particular recognition of the present invention that the improvement is achieved by the combined inclusion of aniline substituted with one or more groups capable of giving a Hammett sigma value.

Positive Hammett sigma values indicate substituents that can make the phenyl ring electron-withdrawing, while negative Hammett sigma values indicate substituents that can make the phenyl ring electron-donating. Hydrogen is determined to have a Hammett sigma value of zero. Lange flan
dbook of ChemtsLry, 12th
Ed.

McGraw-Old 11, 1979. Table 3-1
2. pp. 3-135 to 3-138 list Hammett sigma values for many commonly found substituents. By algebraically summing the Hammett sigma values of the various ring substituents of aniline (i.e., ring substituents other than the one required amine substituent), the Hammett sigma values derived from the electron-withdrawing properties of the ring substituents are determined. is determined.

It is noteworthy that the amine substituent forming the aniline is an electron donating substituent. For example, primary amine group (-NHz); alkylamino (for example, NII
CH21NHCH2CH3, and -Nll -n -C
, l+9); as well as tertiary amine groups such as dialkylamino [e.g.
The Hammett sigma value of the class amine group is -0,04 to -0,
The range is 83, but it is generally on the negative side of -0 and 20. While not intending to be bound to any particular theory to explain the effect, increased effectiveness conferred by the aniline initiator enhancer, it is important to note that the electron-donating and electron-withdrawing groups attached to the phenyl ring of aniline are It seems likely that the molecular polarization created by the presence of both 1 and 2 may play a role in the observed enhancement in initiation activity.

In a preferred form, the aniline contains a single substituent that exhibits a Hammett sigma value greater than +0.20.

The substituents exemplified below (with Hammett sigma values at the meta position additionally indicated) are illustrative of useful electron-withdrawing substituents that can be used as sole aniline ring substituents.

cyano (σ = +0.61), alkylcarbonyl substituents (e.g. acetyl σ = + 0.38 and trifluoroacetyl σ = + 0.65), arylcarbonyl substituents (e.g. phenylcarbonyl σ = + 0
．． 34), oxycarbonyl substituents including alkoxycarbonyl and trioxycarbonyl substituents (e.g., methoxycarbonyl σ = + 0.32, ethoxycarbonyl thiocyanate (σ = + 0.63), behaloalkyl substituents (For example, trichloromethyl σ = + 0
．． 47, and trifluoromethyl σ = + 0.47)
, perfluoroalkylthio substituents (e.g. trifluoromethylthio σ = + 0.35), sulfamoyl substituents including alkylsulfamoyl and trifluorosulfamoyl substituents (e.g. sulfamoyl σ = + 0.46), carbonylthio substituents (e.g. acetylthio σ = + 0.39), carbamoylthio substituents (e.g. carbamoylthio σ = + 0.34)
, alkoxythio and aryloxythio substituents (e.g. methoxythio σ=+0.52) and alkylsulfonyl and arylsulfonyl iftA groups (e.g. methylsulfonyl σ=+0.52).
+0.68, and hyphenylsulfonyl σ = 100.67
) containing sulfonyl substituents.

It also includes those in which multiple rings are substituted with these substituents.

In addition to the highly electron-withdrawing substituents described above, the aniline ring is
Contains ring substituents that have a Hammett sigma value derived from electron withdrawing property of less than +0.20, but not necessarily, provided that a true Hammett sigma value derived from electron withdrawing property of at least +0.20 is maintained. You may do so. Typical simple substituents and their published Metahammett sigma values are: methyl σ = − 0.07, ethyl σ =
- 0.07, n-propyl (1 = - 0.05
, i-propyl, IF = − 0.07, n-butyl 6 = − 0.07, sec-butyl σ = − 0.
07, primary and secondary alkyl substituents.

These alkyl substituents are convenient for their synthesis,
For this purpose, although it is electron-donating, it is contemplated. Alkyl substituents containing tertiary carbon atoms, especially tertiary alkyl groups, tend to be even more electron-donating and are not preferred. Aryl groups such as phenyl, α-naphthyl, and β-naphthyl groups are contemplated (e.g., phenyl σ=
+0.06). Other useful and specifically contemplated hydrocarbon substituents include alkaryl substituents (e.g., p-methylphenyl), aralkyl substituents (e.g., benzyl σ-
-0,05, and phenethyl), alkenyl substituents (e.g. vinyl σ = + 0.02), alkenyl substituents! (For example, 2-phenylvinyl σ = + 0.1
4), alkynyl substituents (e.g. ethynyl σ=+0.
21, propargyl and 2-butynyl) and aralkynyl substituents (e.g. phenethynyl σ=+0.14). Haloalkyl substituents (e.g. bromomethyl, chloromethyl σ=-0,12, fluoromethyl, and iodomethyl), haloaryl substituents (e.g. eva, p-bromophenyl, m-bromophenyl, and p-chlorophenyl), and hydroxyalkyl substituents Substituted hydrocarbon substituents are also contemplated, such as groups (eg, hydroxymethyl σ = +0.08). Oxygen substituents or substituent moieties of hydrocarbon substituents are specifically contemplated - i.e. hydroxy (σ = +0.10), alkoxy (e.g. methoxy, ethoxy σ = + 0.07, n-propoxy d = + 0.07, i-propoxy σ = +
o, oo, n-butoxy σ--0,05, cyclohexoxyglucose 0.29, cyclohexylmethoxy σ=+
0.18 and trifluoromethoxyσ = + 0.36
) as well as aryloxy (e.g. phenoxy σ= +
0.25). Halogen substituents are contemplated - i.e. bromo (σ = +0.39), chloro (σ = +0.3
5), fluoro (σ = + 0.34) and iodine (
σ = + 0.35). Amide (σ=+0.25)
, methylamide (σ = + 0.21), phenylamide (σ = + 0.22), and ureido (σ = +
Amide substituents such as 0.18) are also contemplated.

When electron-donating or weakly electron-withdrawing substituents are used, they in each case combine to form a true Hammett that derives from the values of the various substituents other than the one 7-mino substituent required to form the aniline. Sigma values are used in such a way that they are thicker than +0.20. Meta Hammett sigma values are given, but in many instances the para Hammett sigma values are not significantly different and are published anyway. The ortho Hammett sigma value is virtually identical to the Hammett sigma value for the -g to para position.The meta, ortho and para positions of various substituents to aniline are It is determined based on the position of the amino group formed. To minimize molecular bulk, the aliphatic components of the various ring substituents each contain 6 or fewer carbon atoms, and the aromatic components each contain 10 or fewer carbon atoms. is generally preferred.

The azinium salt activators used in the imageable compositions of the present invention can take any convenient form and can be selected from among the known azinium salt activators.

He5eltine et al and jenki
U.S. Patent Nos. 27,922 and 27,925, 5 pech and Fa.
British Publication No. 2.083,832A of Rid, and Re
5earch Disclosure, Vol, 200
．． Dec, 1980. The azinium activators disclosed by Item 20036 (supra) provide various examples of useful azinium activators.

Azinium activators include azinium nuclei such as pyridinium, diazinium or triazinium nuclei. The azinium nucleus includes one or more aromatic rings, typically a carbocyclic aromatic ring fused with an azinium ring. In other words, the azinium ring includes quinolinium,
Includes isoquinolinium, benzodiazinium and naphthodiazonium nuclei. In order to achieve the highest achievable activation efficiency per unit weight, it is preferred to use monocyclic azinium nuclei.

Quaternization of the nitrogen atom of the azinium ring
ing) The substituent can be released as a free radical based on electronic transition from the photosensitizer to the azinium activator.

In a preferred form, the quaternizing substituent is an oxy substituent. The oxy substituent (-0-R) quaternizing the ring nitrogen atom of the azinium nucleus can be selected from various synthetically convenient oxy substituents.

Component R is, for example, an alkyl group such as methyl, ethyl, butyl, and the like. This alkyl group may be substituted. For example, alfurkyl (eg, hensyl and phenethyl) and sulfoalkyl (eg, sulfomethyl) groups are contemplated. In other forms, R is -C(0)
-R' is an acyl group, such as the group where R1 can take various forms of the alkyl and aralkyl groups described above. Furthermore, R1 is an aryl group such as phenyl or naphthyl. Aryl groups may be substituted. For example, R1 is a triyl or xylyl group. R is
It typically has an alkyl component on each side preferably containing from 1 to 8 carbon atoms and an aryl component preferably containing from 6 to 10 carbon atoms in each case, with 1 Contains ~18 carbon atoms. The highest activity levels are achieved when the oxy substituent (-0-R) contains 1 or 2 carbon atoms.

The azinium nucleus need not contain substituents other than quaternizing substituents. However, the presence of other substituents does not impair the activity of the activator.

Although it is known to include substituents on the azinium nucleus to directly increase light absorption by the activator, substituents that can accomplish this function are not required.

The photosensitizer ensures the absorption of light and the azinium nucleus, besides the quaternizing substituent, is unsubstituted (and preferably unsubstituted, such as for ease of synthesis or physical handling). Substituted and unsubstituted aryl substituents of 6 to IO carbon atoms (e.g. phenyl or naphthyl) and 1 to 18 carbon atoms, preferably 1 to
It may be substituted with relatively simple groups, such as groups selected from substituted and unsubstituted alkyl and alkenyl groups of 8 carbon atoms. Activators that do not have dye chromophores and therefore have limited visible light absorption capacity offer the advantage of improved stability when exposed to synthesis and/or handling regimes. For example, these activators remain stable when synthesized and handled in unfiltered room light.

To the extent that substituents other than quaternized nitrogen atom substituents are present in the azinium salt used, these substituents are preferably electron-withdrawing or neutral. When a substituent other than a quaternized nitrogen atom substituent is present that is electron donating, its effect is to shift the reduction potential of the activator to a more negative value.

Electron-donating substituents are useful in combination as photosensitizers because photosensitizers have reduction potentials of up to 0.1 volts and more on the positive side relative to the reduction of azinium salt activators. This clearly has the effect of limiting the selection of dyes that can be used. However, many photosensitizers with sufficiently negative reduction potentials remain useful in combination with azinium activators having electron-donating substituents. A wide selection of substituents for the azinium salts used in the invention is thus possible. In view of the above, suitable azinium ring substituents are represented by one or a combination of the substituents listed for the aniline enhancers above.

A convenient charge balance counterion (charge balance counterion)
ingcounter-1on) can be used to complete the activator. Both weakly dissociated and highly dissociated counterions are shown to be useful.

Counterions can be selected to be compatible with residual components of the imaging system. For example, relatively undissociable fluorinated carboxylate counterions, particularly perfluorinated carboxylate counterions, are advantageously used with azinium activators introduced into olefinic media, particularly those described below.

Nevertheless, it is believed that the highest level of activity can be attributed to the azinium activator dissociating from the charge-balanced counterion in the imageable composition. Although variations in ion dissociation can be achieved by various choices of solvent, film-forming components, acidity, etc., generally higher levels of counterion dissociation are achieved with hexafluorophosphate, tetrafluoroborate, verchlorate, para-toluene, etc. Occurs with more electronegative counterions such as sulfonates, halides, sulfates and similar electronegative anilines.

Any photosensitizer known to be useful with azinium salt activators can be used in the imageable compositions of the present invention. For example, 5 pecht and Fari
d British Publication No. 2.083,832A or Re5ea
rchDisc1osure, Vol, 200. Dec
, 1980. All of the photosensitizers disclosed by Item 20036 (supra) can be used.

Dye photosensitizers are particularly preferred. The term "dye" is used in art-recognized usage to refer to a soluble substance capable of absorbing visible light and thereby exhibiting a visible hue. The dye photosensitizer used can be selected from the class of known dyes which exhibit a reduction potential that is up to 0.1 volt more positive with respect to that of the azinium activator.

Amino-substituted photosensitizers containing certain keto dyes, particularly ketocoumarin dyes and ketomethylene dyes (merocyanine dyes), which have major absorption peaks at wavelengths up to 550 ni and exhibit relatively high intersystem cross-efficiency, have azinium activity. 5pe is useful as a co-initiator in combination with a co-initiator.
Cht and Farid British Publication Tube 2.083.
No. 832A, dyes with a major absorption peak at wavelengths longer than 550 nm (hereinafter referred to as longer wavelength dyes) that satisfy the required reduction potential are
It has now been recognized that it is a more efficient photosensitizer when used as a co-initiator with an azinium salt activator. In addition, both longer wavelength dyes and shorter wavelength dyes that satisfy the required reduction potential (these are 550
nrrI (which exhibits a major absorption peak at a shorter wavelength) was found to be a more efficient photosensitizer even when exhibiting a relatively low intersystem cross-over efficiency, i.e., less than 10%. It was done.

It is therefore clear that dyes useful as photosensitizers can exhibit desirable hues suitable for imaging applications.

It is generally preferred to use subtractive primary dyes as photosensitizers, especially when producing polychromatic images. The primary color dyes of the subtractive color method are blue in the spectrum (400-500 nm),
Green (500~600r+m) or red (60
has a main absorption peak in one of the ranges (0 to 700 nm);
Indicates yellow, magenta, or cyan.

Particularly notable dye types that can be selected include coumarin (including ketocoumarins and sulfonocoumarins) dyes;
These are merocyanine dyes, merostyryl dyes, oxonol dyes, and hemioxonol dyes. Dyes from each of the above classes all contain a keto group on the blue absorbing chromophore and are therefore all designated keto dyes. Furthermore, it is a particular recognition of this invention that the dye sensitizers useful in the practice of this invention need not be keto dyes. That is, the keto group in the blue-absorbing chromophore of the dye is not essential. Non-keto dyes include a variety of dye types including non-keto polymethine dyes, rhodamine dyes, anthracene dyes, acridine dyes, aniline dyes and azo dyes. Non-keto polymethine dyes include cyanine, hemicyanine and styryl dyes.

In one preferred embodiment of the invention, the dye photosensitizer is
cyanine, merocyanine, complex cyanine and merocyanine (i.e. l-li, tetra- and polynuclear cyanine and merocyanine), oxonol, hemioxonol,
Selected from polymethine dye classes including styryl, merostyryl, and streptocyanin.

Cyanine dyes consist of two basic heterocyclic nuclei, such as azolium or azinium nuclei, linked by a methine bond;
For example, pyridinium, quinolinium, inquinolinium, oxacillium, thiazolium, selenazolium,
Imidazolium, pyrazolium, virolium, indolium, 3H-indolium, imidazolium, oxadiazolium, thiadioxazolium, benzoxazolium, benzothiazolium, benzoselenazolium, penzotellazolium, benz Imidazolium, 3H- or IH-benzoindolium, naphthoxazolium, naphthothiazolium, naphthoselenazolium, naphthoxazolium, carbazolium, pyrrolopyridinium, phenanthrothiazolium, and acenaphthothiazolium Including those derived from quaternary salts.

Examples of basic heterocyclic nuclei satisfy formulas 1 and 2.

- shadow [wherein Z is oxazoline, oxazole, benzoxazole, naphthoxazole (e.g. naphtho[2,1
-di]oxazole, naphtho[2゜3-di]oxazole and naphtho[1,2-di]oxazole), oxadiazole, thiazoline, thiazole, benzothiazole, naphthothiazole (e.g. naphtho[2,1-di]oxazole) thiazole), thiazoloquinoline (e.g. thiazolo C4
, 5-bi]quinoline), phenanthrothiazole, acenaphthothiazole, thiadioxazole, selenapurine, selenazole, benzoselenazole, naphthoselenazole (e.g., natu[1,2-di]selenazole),
Penzotelllazole, naphthotellazole (e.g. naphtho[l,2-di]telllazole), imidacillin, imidazole, benzimidazole, naphthoimidazole (e.g. naphtho[2,3-di]imidazole), 2-
or 4-pyridine, 2- or 4-quinoline, ■- or 3
-isoquinoline, benzoquinoline, 3H-indole,
Represents a group of elements necessary to complete a cyclic nucleus derived from basic heterocyclic nitrogen compounds such as IH- or 3H-benzoindole and pyrazole, which nucleus is composed of hydroxy, halogen (e.g., fluoro, chloro). , bromo and iodo), alkyl or substituted alkyl groups (e.g. methyl, ethyl, propyl, isopropyl, butyl, octyl, dodecyl, octadecyl, 2-hydroxyethyl, 3-sulfopropyl, carboxymethyl, 2-cyanoethyl and tri- fluoromethyl), aryl or substituted aryl groups (e.g. phenyl, l-naphthyl, 2-
naphthyl, 4-sulfophenyl, 3-carboxyphenyl and 4-biphenylyl), aralkyl groups (e.g.
hensyl and phenethyl), alkoxy groups (e.g. methoxy, ethoxy and isopropoxy), aryloxy groups (e.g. phenoxy and 1-naphthoxy), alkylthio groups (e.g. methylthio and ethylthio), arylthio groups (e.g. phenylthio, p- tolylthio and 2-naphthylthio), methylenedioxy, cyano, 2-thenyl, styryl, amine or substituted amine groups (e.g. anilino, dimethylamino, diethylamino and morpholino), acyl groups (e.g. formyl,
Q may be substituted on the ring by one or more of a wide variety of substituents, such as (acetyl, benzoyl and hensensulfonyl); Q is pyrrole, indole, carbazole, benzindole, pyrazole, indazole and represents a group of elements necessary to complete a cyclic nucleus derived from a basic heterocyclic nitrogen compound such as pyrrolopyridine.

R represents an alkyl, aryl, alkenyl, or aralkyl group with or without substituents (eg, carboxy, hydroxy, sulfo, alkoxy, sulfato, thiosulfato, phosphono, chloro, and bromo substituents).

L is in each case independently a substituted or unsubstituted methine group - for example -CR'= group (wherein R3 represents hydrogen when the methine group is unsubstituted; most commonly represents alkyl or phenyl of 1 to 4 carbon atoms).

q is 0 or 1. ] The cyanine dye may contain two heterocyclic nuclei of the type shown in formula 1 linked by methine bonds containing an odd number of methine groups, or a methine bond containing an even number of methine groups. may contain heterocyclic nuclei according to each of formulas 1 and 2 linked by , in which case the methine group may take the form -CR'= as described above. In general, in polymethine dyes, particularly cyanine dyes, the larger the number of methine groups bonding to the nucleus, the longer the absorption wavelength of the dye becomes.

For example, a dicarbocyanine dye (a cyanine dye containing 5 methine groups bonding two basic heterocyclic nuclei) is a dicarbocyanine dye (a cyanine dye containing 5 methine groups bonding two basic heterocyclic nuclei); cyanine dye containing a methine group) [This shows a longer absorption wavelength than a simple cyanine dye (a cyanine dye containing one methine group linking two basic heterocyclic nuclei)] also exhibits a long absorption wavelength. Carbocyanine and dicarbocyanine dyes are longer wavelength dyes, while simple cyanine dyes are typical yellow dyes, but with appropriate selection of nuclei and other components that can bathochromically shift absorption. This allows it to exhibit absorption up to a maximum wavelength of about 500 nm. One technique for bathochromically shifting the absorption maximum of polymethine dyes in general, and cyanine dyes in particular, is to include oxocarbon crosslinking nuclei in the methine bonds. Exemplary oxocarbon bridging nuclei can take the form shown by the following formula: -''-〇〇工■〇-, where n is an integer of 0, 1, or 2.

Merocyanine dyes are produced by bonding one of the basic heterocyclic nuclei of the above cyanine dye type to the acidic ketomethylene nucleus through the above methine bond (containing zero, two, or a larger even number of methine groups). There is. Zero methine dyes that do not contain methine groups in their internuclear bonds
ine dyes) indicates an internuclear double bond in one resonance form and a single bond in the other resonance form. In either resonance form, the nuclear binding sites are formed by methine groups forming part of each nucleus. Zeromethine polymethine dye is a yellow dye.

An exemplary acidic nucleus is one that satisfies Formula 4.

Formula -↓ 0 In the formula, G1 is an alkyl group, a substituted alkyl group, an aryl group, a substituted alkyl group, an aralkyl group, an alkoxy group,
represents an aryloxy group, a hydroxy group, an amino group or a substituted amino group, where exemplary substituents can take the various forms described with respect to formulas 1 and 2.

G2 represents one of the groups described for G1, and further represents a cyano group, an alkyl or ester-sulfonyl group, or a group represented by -〇-G'; G2 together with Gl represents 2; .4-oxazolidinone (e.g. 3-ethyl-2°4-oxazolidinedione),
2.4-thiazolidinedione (e.g. 3-methyl-2
, 4-thiazolidinedione), 2-thio-2,4-oxazolidinedione (e.g., 3-phenyl-2-thousand-2,4-oxazolidinedione), 3-ethylrhodanine, 3-phenylrhodanine, 3- (3-dimethylaminopropyl)rhodanine and 3-carboxymethylrhodanine, hydantoins (e.g.
1,3-diethylhydantoin and 3-ethyl-1-phenylhydantoin), 2-thiohydantoin (e.g. 1-ethyl-3-phenyl-2-thiohydantoin,
3-hebutyl-1-phenyl-2-thiohydantoin and arylsulfonyl-2-thiohydantoin), 3
-methyl-1-phenyl-2-virazolin-5-one,
2-Birapurin- such as 3-methyl-1-(4-carboquinbutyl)-2-pyrazolin-5-one, 3-methyl-1-(4-sulfophenyl)-2-birapurin-5-one 5-one, 2-isoxazolin-5-one, (
3-phenyl-2-isoxazolin-5-one), 3,5-pyrazolidinedione (e.g. 1,2-diethyl-3,5-pyrazolidinedione, and 1°2-diphenyl-3, 5-pyrazolidinedione), 1,3-indanedione, 1,3-dioxane-4,6-dione,
1,3-cyclohexanedione, barbylic acid (e.g., l-ethylbarbylic acid, and 1,3-diethylbarbylic acid), and 2-thiobarbylic acid (
For example, the elements necessary to complete a cyclic acid nucleus such as those derived from 1゜3-diethyl-2-thiobarbylic acid and 1゜3-bis(2-methoxyethyl)-2-thiobarbylic acid). represent

Useful hemicyanine dyes are essentially the same as the merocyanine dyes described above, except that the ketomethylene group in formula 4 is replaced with a group shown in formula 5 below.

The following blank formula -j- [wherein G3 and G4 may be the same or different and represent alkyl, substituted alkyl, aryl, substituent ring or aralkyl as shown for the ring substituent in formula 1] or G3 and G4 together represent pyrrolidine, 3-pyrroline, piperidine, piperazine (e.g. 4-methylpiperazine and 4-phenylpiperazine), morpholine, 1,2,3,4-tetrahydroquinoline , decahydroquinoline, 3-azabicyclo(3
, 2, 2) complete ring systems derived from cyclic secondary amines such as nonane, indoline and hexahydroazepine].

Useful hemioxonol dyes include ketomethylene nuclei as shown in formula 4 and nuclei as shown in formula 5 linked by methine groups as described above containing one or more odd number of methine groups. shows.

Useful merostyryl dyes include ketomethylene nuclei as shown in formula 4 bound by methine groups as described above containing one or more odd number of methine groups and formula 6.
Indicates a nucleus as shown in .

The cyanine, merocyanine, -mycyanine, hemioxonol, and merostyryl dyes described above are intended to represent the simpler structures of useful polymethine dyes. It is generally recognized that substituents can join the nucleus and the methine linkage to form additional ring structures. Additionally, the dye can contain three or more nuclei. For example, a heteropolar cyanine dye can be formed by replacing a merocyanine dye at its methine linkage with a secondary basic heterocyclic nucleus in the form of a cyanine dye. Additionally, various substituents that do not form part of the dye chromophore can be used as desired to adapt the dye physical properties, particularly hydrophobicity and hydrophilicity, to suit the particular film-forming component used. It can be changed. As the aliphatic component of the dye, many carbon atoms (e.g. about 6 to 2
The dye can be made more olefinic by choosing a hydrocarbon group having 0 carbon atoms), whereas a hydrocarbon group containing a lower number of carbon atoms (e.g. 1 to 5 carbon atoms) and especially those with dipolar substituents make the dye more hydrophilic. The aromatic component of the dye typically contains 6 to 10 carbon atoms.

In addition to being dyes as defined above, dyes are useful as photosensitizers in the present invention by up to 0.
At 1 volt, it must exhibit a reduction potential that is more positive than that of the azinium salt activator with which it is used. Electronic transfer from the photosensitizer to the activator is efficiently accomplished when the reduction potential of the longer wavelength dye is more negative than that of the photoactivator. Furthermore, energy transfer can still occur when the reduction potentials of the photosensitizer and activator are equal. Furthermore, effective outcomes are observed when the reduction potential of the photosensitizer is to a limited extent more positive than that of the activator.

In order to select a suitable dye for use as a photosensitizer, it is necessary to compare the reduction potential of the dye with the azinium activator to be used. In the vast majority of cases, an unambiguous determination of reduction potential does not require confirming that an appropriate relationship of reduction potentials exists. Without taking into account that in the few instances where the reduction potential of the dye is sufficiently positive relative to that of the activator that an unambiguous determination of the reduction potential is desired, it may vary as a function of the method by which the reduction potential is measured. must not. To provide a special standard for reduction potential measurements, J. Lenhard, Measurement of
Rever-sible Electric P
otentials for Cyanine
Dyesby the Use of Phase-5
elective 5econd HarmonicA
CV Voltammetry', Journal of
ImagingScience.

Vol, 30. No, 1. Jan, /Feb, 1986
The method described in is used.

In addition to considering the use of dyes as photosensitizers that include longer wavelength dyes and satisfy the reduction potential relationships described above, the present invention particularly provides low intersystem cross-over efficiency to the triplet state;
That is, consideration is given to the use of keto dyes, particularly yellow keto dyes, which exhibit intersystem cross-over efficiencies of less than 10%. In other words, it is the recognition of the present invention that dyes with limited excited state lifetimes are still efficient photosensitizers.

Measurements of intersystem cross-over efficiency to triplet states are generally known and reported in the art and do not form part of the present invention. The technique for measuring this parameter is 5 pec
ht, Martic, and Farid, “8Ne5
C1ass of Triplet 5ensitiz
ers”, Tetra-hedron.

Vol, 38. pp. 1203-1211.1982 and the references cited therein.

The remaining basic components of the imageable compositions of this invention are organic components that contain sites of ethylenically unsaturation and can be selectively cured by addition at the sites of ethylenically unsaturation. vinyl monomers containing a wide variety of ethylenic unsaturations,
Vinyl oligomers and polymers are known and useful in imaging systems according to the present invention. Specific selections of curable organic components are discussed below with reference to their preferred imaging systems.

In a preferred embodiment of the invention, the imageable composition is a negative working photoresist or a negative working photoresist.
esist). The organic component of the negative working photoresist acted upon by the co-initiator contains ethylenic unsaturation and can be selectively immobilized by undergoing a curing addition reaction at the ethylenically unsaturated site to form a known negative working photoresist organic film. It can take the form of ingredients.

Immobilization is provided by initiation of polymerization of monomers containing ethylenic unsaturation or by initiation of crosslinking of linear polymers or oligomers containing ethylenic unsaturation. For example, Jenkins et al.
-1tine e-real U.S. Reissue Patent No. 27,92
The monomeric or crosslinkable polymeric film-forming components disclosed in No. 5 and No. 27,922, respectively, are suitable for use in the imaging compositions of the present invention. Tan
etal U.S. Pat. No. 4,289,842 discloses negative working curable imaging compositions containing photosensitive acrylate copolymers containing pendant groups such as alkenyl groups with ethylenic unsaturation. There is. Lindley U.S. Patent No. 4,590.147
No. 5, No. 1, No. 1, No. 1, No. 1, No. 1, No. 1, No. 1, No. 1, No. 1, No. 1, No. 1, No. 1, No. 1, No. 1, No. 1, No. 1, No. 1, No. 1, No. 3, No. 1, No. 1, No. 1, No. 1, No. 1, No. 2, and No. 1, No. 1, No. 1, No. 1, No. 2, No. 1, No. 1, No. 1, No. 1, No. 1, No. 1, No. 1, No. 1, No. 1, No. 1, No. 1, No. 1, No. 1, and 2, Discloses vinyl oligomers that can be used as film-forming components in the curable imaging compositions of the present invention. Useful film-forming components containing vinyl monomers include Fuerniss, U.S. Pat. No. 4,497,889;
No. 4 and Anderson et al.
No. 535,052. Kosar Li
ght-3ensistive System, John
Wiley & 5ons, 1965 further describes a variety of useful film-forming components for use in the practice of this invention, including ethylenically unsaturated monomers and polymers.

Preferred film-forming components consist of at least one addition-polymerizable ethylenically unsaturated compound having a boiling point above 100'C at normal pressure, preferably used in combination with a polymeric antagonist. Ethylenically unsaturated compounds (typically monomers) and polymeric binders range from 3% to 97% by weight of the film-forming component and from 97% to 3% by weight of the film-forming component. may be used together in widely varying proportions, including polymeric binders. Another polymeric binder, although preferred, is not essential to the film-forming component and is most commonly not used when the ethylenically unsaturated compound is itself a polymer.

Chang, U.S. Pat. No. 3,756,827, col.
is listed. In particular, ester monomers containing ethylenic unsaturation are shown in later examples. A similar example is Chambers U.S. Patent No. 4,24
Mention may also be made of the ethylenically unsaturated diester polyhydroxy polyethers described in No. 5.031.

Organic polymer binders that may form part of the film-forming component of photoresists include (1) polyesters, including those based on terephthalic acid, isophthalic acid, cepatic acid, adipic acid, and hexahydroterephthalic acid; (2) nylons; or polyamides; (3) cellulose ethers and esters; (4) polyaldehydes; (5) high molecular weight ethylene oxide polymers - e.g.
(6) polyurethanes; (7) polycarbonates; (8) synthetic rubbers - e.g. homopolymers and copolymers of butadiene; and (9) polyalkylenes - e.g. polyethylene. and polypropylene; poly(vinyl alcohol); poly(vinyl ester) - e.g. poly(vinyl acetate); polystyrene; poly(acrylic and methacrylic acids and esters) - e.g. poly(methyl methacrylate) and poly(ethyl acrylate); Included are homopolymers and copolymers formed from monomers containing ethylenically unsaturation, such as polymers of various ethylenically unsaturated monomers, such as copolymer versions of .

Of course, the above is only a list indicating the most common curing ingredients. Other curing components include, for example, those specifically shown in the Examples below.

In addition to the curing component and coinitiator, the imaging composition may contain one or more of the known additives such as thermal inhibitors, colorants (dyes and pigments), plasticizers, fillers, etc. Can include combinations.

To facilitate coating onto a support, the film-forming components, co-initiator, and additives, if any, are usually dispersed in a solvent to form a solution or slurry, and the liquid is removed by evaporation after coating. . Any solvent that is inert to the film-forming components and photoresist additives can be used for this purpose. Solvents include N,N-dimethylformamide; N,N-dimethylacetamide; alcohols such as methanol, ethanol, butanol, etc.; ketones such as acetone, cyclohexanone and butanone;
Esters such as ethyl acetate and ethyl benzoate; ethers such as tetrahydrofuran and dioxane; chlorinated aliphatic hydrocarbons such as methylene chloride and 1,2-dichloroethane; aromatic hydrocarbons such as benzene and toluene; A wide variety of organic liquids can be selected, including fluoride, other solvents such as chlorobenzene, as well as mixtures of various solvents.

The support coated with photoresist can take any convenient known form. For example, photoresists can be used to define patterns during the assembly of electronic components. In this example, the support may take the form of a printed circuit board or a semiconductor chip, typically only partially assembled into a finished product. In other examples, the curable imaging composition can be coated onto a simple single support such as glass, ceramic, metal, cellulose paper, fiberboard or polymeric support. Special supports include alumina blasted aluminum, electrolytic aluminum, alumina blasted poly(ethylene terephthalate) film, poly(vinyl alcohol) coated paper, cross-linked polyester coated paper, nylon, glass, cellulose acetate film, lithographic paper. Includes heavy-duty paper such as and similar materials.

In perhaps their most commonly used form, curable imaging compositions are coated onto a support in liquid form;
It is usually evaporated and dried by heating to create a uniform coating. Often, especially in the manufacture of semiconductor devices,
The support is rotated using centrifugal force to ensure uniformity of drying of the photoresist prior to drying. After exposure to actinic radiation, an addition reaction occurs at the ethylenically unsaturated sites of the film-forming component and the liquid developer is brought into contact with the coated support and exposed to actinic radiation. Selectively remove the photoresist in the areas that were not removed.

The liquid developer may be any known liquid capable of selectively removing photoresist in unexposed areas. The coated photoresist may be sprayed or flushed with a developer for selective removal.
h) , F & scraped, immersed or otherwise treated. In its simplest form, the liquid developer is the same liquid used as the solvent in coating the photoresist. Methoxyethyl acetate and ethoxyethyl acetate are common developers. Aqueous developers such as miscible combinations of water and alcohol are also commonly used, usually in proportions of 20-80% water and 80-20% alcohol. Examples of water-miscible alcohols include glycerol, benzyl alcohol, 1.2-7" lopanediol,
Included are ethers derived from glycols such as 5ec-butyl alcohol and dihydroxy poly(alkylene oxide).

U.S. Pat. No. 3,70 to Martinson et al.
Lactone developers such as those disclosed in US Pat. No. 7,373 can be used. Selection of optimal developers for particular curable imaging compositions is disclosed in the various patents mentioned above that indicate particular film-forming components.

In another method of use, the photoresist is coated onto a support and a releasable cover sheet is coated thereon. End users typically purchase photoresists as articles rather than liquid compositions. 711 cover sheet
After release, the photoresist layer, together with its support, is laminated to the substrate on which the image-like pattern is desired. After patterned exposure to actinic radiation through the support, the support is stripped from the substrate leaving the photoresist in an imagewise pattern on the substrate.

In yet another method of use, the photoresist is coated onto a modified support surface to facilitate electroless metal deposition. Also, a peelable cover sheet is placed over the photoresist coating.

In this use, imagewise exposure to actinic radiation occurs through the cover sheet and the cover sheet is then peeled off. When the cover sheet is removed, the photoresist is selectively removed and the remaining photoresist defines the desired pattern. Metal plating then turns the support into an article with a metal pattern thereon. The application of nine letters is in the formation of electrical circuits.

Any known ratio of activator to film-forming component may be present in the curable imaging compositions of this invention. For practical purposes, the activator concentration is conveniently determined in moles of activator per dry duram of solids. Here, the dry solids consist of film-forming components and small amounts of various additives, excluding liquid components introduced to facilitate coating.

Typically about 2X10-2 per gram of dry solids
5X10"5 moles, most preferably from about 5X1O-5
There are 20XIO-5 moles of activator.

In the practice of the present invention, enhancers include:
They can be included in the image-forming composition in conventional effective amounts. Typically from about 0.1 to 1 per mole of activator.
0 mole is used, preferably about 0 mole per mole of activator.
．． 5-5 mol is used. Of course, it is possible to use higher amounts.

The photosensitizer can be present at any concentration capable of enhancing the response of the photoresist to ultraviolet or visible light. Photosensitizers); degrees can vary widely, but are generally about 5X10-
It is contemplated to use the photosensitizer at a concentration in the molar range from ' to lXl0-'. The preferred photosensitizer concentration is dry solids 1
ranging from 10-6 to 5 x 10-5 moles per gram, with optimum concentrations generally ranging from about 2
It is in the range of 2X10-' moles.

By including an imaging dye or dye precursor in the photoresist composition, it is possible to use the various photoresists described above to form either simply monochrome or multicolor dye images. Following the development of the photoresist,
A retained dye image is revealed by the remaining photoresist coating on the substrate. The colored area corresponds to the exposed area. color proofing
Multicolor images, such as those used for It is formed.

In the imaging system described above, only a single coating layer is required for imaging. However, the imaging system of the present invention can use multiple layers.

For example, instead of mixing the imaging dye with the film-forming components as described above, a separate imaging dye layer can be coated between the substrate and the photoresist layer. During exposure and development of the image, the photoresist is removed in the exposed areas. Where the photoresist remains, the underlying imaging dye remains in its original fixed state; in other areas the dye may be removed or bleached by washing or other known techniques.

In the photoresists described above, the curable organic component containing ethylenically unsaturated sites is the film-forming component.

However, in certain preferred imaging systems of the present invention, the curable organic component is either in contact with the surrounding continuous phase or
It may exist as discrete or internal phase-forming microcapsules separated by intervening rupturable capsule walls. Although microcapsules containing a curable organic component, a co-initiator, and an imageable dye or dye precursor, respectively, can be coated to form a monochromatic image, the present invention provides Allows the formation of polychromatic images using a single layer of microcapsules. The microcapsules form a separate packet of material so that in the same layer, microcapsules containing dye sensitizers that absorb at different positions in the visible spectrum and different imaging hues (
image-forming dyes (or their precursors). For example, as a single layer on a substrate,
(a) microcapsules containing a yellow dye photosensitizer and a yellow or blue imaging dye or a precursor thereof;
(b) microcapsules containing a magenta dye photosensitizer and a magenta or green imaging dye or its precursor; (c) microcapsules containing a cyan dye photosensitizer and a cyan or red imaging dye or its precursor; It is intended to coat the capsule. Except for the choice of dye photosensitizer and imaging dye, the microcapsules are otherwise identical. In this way, by simply mixing three different populations of microcapsules, polychromatic images can be obtained as easily as monochromatic dye images.

Monochromatic and polychromatic imaging according to the present invention is the same, except that the microcapsule population is mixed prior to hue selection and coating of the components. Thus, for simplicity, the following description will refer to monochromatic imaging, but the description is applicable to both monochromatic and multicolor imaging, except where indicated otherwise.

Microcapsules can be used to form retained or transferred dye images. Additionally, preformed dyes or preferably dye precursors can be included in the microcapsules.

In residual imaging systems, a receiving layer is coated onto a substrate and a layer of microcapsules is coated thereon. Each coated microcapsule therein is exposed to light that is absorbed by the dye sensitizer and releases free radicals by the azinium activator, resulting in hardening of the organic component containing ethylenic unsaturation. Subsequently, uniform destruction of all coated capsules occurs by passing the exposed element between pressure rollers, removing the imaging dye or its precursor from the microcapsules that were not exposed to light and therefore not internally cured. will be moved.

The released dye or dye precursor diffuses into the receiving layer. When the imaging dye is contained in microcapsules, the receiving layer may form a convenient transparent dye-permeable material. For example, the dye may be in a hydrophilic colloid layer or a layer of film-forming polymer. Preferably, the image dye is applied to the image receiver.
ipt), a mordant is present in the image-receiving layer.

When the microcapsules contain a dye precursor, the dye imaging layer contains a second component capable of acting with the dye precursor to form an image dye. Hereinafter, one of these two components will be referred to as the chromogen substance, and the other will be referred to as the developer. Either or both are considered dye precursors, with one being located within the microcapsule and the other being located in the dye imaging layer in monochromatic imaging. However, the chromogenic material, which is different in hue from the dye produced for multicolor image formation, is located within the microcapsules. For simplicity, the following description is directed to the chromogenic material contained in the microcapsules and the developer located in the image-receiving layer, but the reverse arrangement is also possible, unless stated otherwise. . The image-receiving layer is similar to the preformed imaging dye image-receiving layer, except that it contains an extra developer.

Transfer dye image systems can be made similar to the residual dye image systems described above, but with the difference in the location of the image receiving layer.

Instead of coating the image receiving layer on the same support as the microcapsules, the image receiving layer is coated on a separate support. In a layered format arrangement, the image-receiving layer and its support become associated with the microcapsule layer and its support at the time of exposure as well as at the time when transfer from the microcapsules to the image-receiving layer occurs. Also, the image-receiving layer and its support do not need to be combined with the microcapsule layer until rupture of the microcapsules occurs. In one arrangement, the image-receiving layer and its support can be used alone as an imaging element or can remain together with the microcapsule layer and its support. In the latter case, the photobleachability of the photosensitizer and the initially colorless form of the chromogenic substance are particularly advantageous.

Generally similar materials can be used to form the microcapsule systems described above with respect to negative working photoresists, the essential difference being the physical continuity of the imaging layer. However, certain materials described below appear to be particularly suitable for use in microcapsule imaging systems and constitute preferred materials.

Preferred curable organic components containing ethylenic unsaturation include:
Compounds containing at least one terminal ethylenic group per molecule, preferably two or more terminal ethylenic groups per molecule are included. Typically they are liquids and also serve as a carrier oil for the chromogenic material in the inner layer. Representative examples of these compounds include ethylenically unsaturated acid esters of polyhydric alcohols such as trimethylolpropane triacrylate.

Preferred curable components include acrylate prepolymers derived from the partial reaction of pentaerythritol with acrylic acid or acrylic esters. Such materials are available from Richardson Com-pany,
MelrosePark+ 111. - For example, R1
-1482 and R1-1483-. Also, Carlick et al., U.S. Pat. No. 3,825.
No. 479, No. 3,759.809 and No. 3.78
Also useful are isocyanate-modified acrylates, methacrylates and itaconic acid esters of polyhydric alcohols, such as those disclosed in No. 3.151.

The chromogenic material used in the present invention is preferably an oil-soluble color product that reacts with a developer to form a dye in the presence of a carrier oil. Representative examples of such chromogenic materials include lactones, lactams, sultones, spiropyrans, substantially colorless compounds containing ester or amide structures.

Particularly preferred chromogenic materials are triarylmethane, bisphenylmethane, xanthene, thiazine, spiropyran and similar compounds thereof. Also useful as chromogenic materials are organic compounds that can be complexed with heavy metals to form dyes, such as copper phthalocyanine. Particular additional and basic dye-forming chromogen materials are disclosed in US Pat. No. 3,920,510, US Pat. No. 4,339,209, and US Pat.

In addition to curable organic compounds, co-initiators and chromogenic substances,
The separate phase or microcapsules can also contain a carrier oil. Preferred carrier oils are weakly polar solvents with a boiling point above 170°C, preferably in the range from 180°C to 300°C. Examples of carrier oils include 1. Alkylated biphenyls (e.g. monoisopropylbiphenyl), polychlorinated biphenyls, castor oil (c
aster oil), mineral oil, deodorized kerosene, naphthenic mineral oil, dibutyl phthalate, dibutyl thumerate, brominated paraffins, and mixtures thereof. Alkylated biphenyls are preferred due to their low toxicity, while brominated paraffins are particularly preferred for halftone imaging when used in combination with trimethylolpropane triacrylate.

A carrier oil is not required. As mentioned above, the curable organic component can achieve mobility that provides the function of a carrier oil in many instances, especially when the curable organic component is sulfuric. The choice of carrier oil depends on the spread of the chromogenic material that is transferred upon destruction of the microcapsules. The carrier oil is based on its ability to impart mobility to the chromogenic material in the absence of hardening of the organic components containing ethylenic unsaturation as well as being non-reactive with the various components of the microcapsules. selected.

internal phase that forms microcapsules
phase) consists of various optional components that provide improved imaging properties, such as curable organic components, optional carrier oils, chromogenic materials, co-initiators and light scattering materials, stabilizers and the like. .

The materials forming the internal phase of the microcapsules are generally present in concentration ranges similar to those described above for photoresists. Generally, the curable organic component comprises at least about 40% by weight of the internal phase, typically about 50% of the internal phase.
Constituting ~99% by weight.

The chromogenic material can be present at any concentration that provides a visible dye image. Generally, useful concentrations are based on the weight of the internal phase;
It ranges from about 0.5 to 20.0% by weight.

The preferred range of chromogenic material for monochromatic imaging is about 2-7% by weight of the internal phase. In multicolor imaging, a somewhat higher concentration of chromogenic material is preferred since only one-third of the microcapsules are utilized to provide maximum image dye concentration of the primary color hues. For example, a maximum density magenta image must be formed using only one-third of the microcapsules containing the chromogen monomer material that forms the magenta dye. The preferred range of chromogenic material for multicolor imaging is about 5-15% by weight of the internal phase. The carrier oil may be present, although not required, at a concentration of up to about 50% by weight of the internal phase, preferably from about 10 to 40% by weight of the internal phase. The co-initiator can be present at the same concentrations as described above for photoresists, where:
The dry solids percent basis corresponds to the internal phase percent basis for microcapsules.

In a preferred embodiment, the microcapsules each contain a wall encapsulating a rupturable periphery in addition to an internal phase. Encapsulation can be performed by any convenient known method. Oil-soluble chromogenic substances are described by Green et al.
U.S. Pat. No. 2,730,456 and U.S. Pat. No. 2.800
gelatin and gelatin derivatives (e.g. phthalated gelatin), gum arabic,
Polyvinyl alcohol and carboxymethyl cellulose wall formers, resorcinol-formaldehyde wall formers as shown in Vassilia-des U.S. Pat. No. 3,914,511, Kiritani
Isocyanate-polyol wall formers, such as those shown in U.S. Pat. No. 3,796,669 of F. et al.
U.S. Patent No. 4,001,140 to oris et al.
No. 4.087.376 and No. 4,089.8
Urea-formaldehyde wall formers, particularly urea-resorcinol-formaldehyde wall formers, as shown in 5hackle U.S. Pat.
5,455, and hydroxypropyl cellulose wall formers. Of course, the wall forming material must be transparent to the exposing radiation. Preferred wall-forming materials are gelatin and gelatin derivatives, as well as ureareducinol-formaldehyde wall-forming materials.

Microencapsulation is accomplished by convenient known techniques including coacervation, interfacial polymerization, polymerization of one or more monomers in an oil, as well as various melt dispersion cooling methods.

Microcapsules are usually chosen to be of such small size that they cannot be individually recognized with the naked eye. The microcapsules have a diameter of about 1 to 25 micrometers (-), depending on the desired image sharpness, the smoothness of the support surface, and the technique used to destroy the microcapsules.
More typically, it ranges from about 3 to 15 diameters. Generally, the sharpness of the dye image increases as the size of the microcapsules decreases. However, smaller microcapsules are less easy to coat onto substrates with rough surfaces and are less easy to break uniformly by mechanical techniques.

The microcapsules are coated with -i at a concentration sufficient to at least cover the surface of the support.

That is, based on the average diameter of the microcapsules, the coverage is selected to provide at least a monolayer coverage of the microcapsules on the support.

Instead of forming microcapsules with separated walls,
Microcapsules containing a composition suitable for coating on a substrate may form an emulsion in which the microcapsules constitute a discontinuous or an internal phase and a binder similar to the wall-forming material described above constitute a continuous phase. It is recognized that it can be manufactured by For example, such microcapsule coatings can be formed using hydrophilic binders such as hardened gelatin and gelatin derivatives.

Reacting with the chromogenic substance (or sub-dye precursor) is
A developer (or secondary dye precursor).

The developer can take the form of any substance that can react with the chromogenic material to create a dye. Developers indicated for the above preferred types of chromogens include clay minerals such as acid clay and activated clay apurgite, organic acids such as tannic acid, gallic acid, and propyl gallate;
Acid polymers such as phenol-formaldehyde resins, condensates of formaldehyde with carboxylic acids containing only one hydroxyl group, zinc salicylate,
Tin salicylate, zinc 2-hydroxynaphthenate, 3.5
- metal salts of aromatic carboxylic acids such as zinc di-tert-butylsalicylate, oil-soluble metal salts of phenol-formaldehyde novolak resins (particularly U.S. Pat. No. 3,67
No. 2,935, No. 3,732.120 and No. 3,
737,410), zinc carbonate, and mixtures thereof.

Preferably, when the developer is coated onto a substrate, the developer is typically dispersed in a binder.

The binder is selected to be a relatively dye-permeable inert material such as poly(vinyl alcohol), gelatin or gelatin derivatives, maleic anhydride-styrene copolymers, starch, gum arabic, or cellulose esters. Generally, known film-forming binders are useful. As mentioned above, a mordant can be included in the developer binder to help fix the dye once formed. Various mordants with particular affinity for gelatin or gelatin derivatives are described by Ilartma
No. 4,315,978.

Although microcapsule-containing imaging systems are described above using chromogenic materials and developers,
If desired, transferable imaging dyes can replace the chromogenic material. An advantage of using a chromogenic material is that the chromogenic material does not need to contain a chromophore to compete with the dye photosensitizer for photon dye capture. Furthermore,
The chromogenic material minimizes coloration of the imaging system in areas where no image dye is formed.

Although described above with respect to a preferred microcapsule imaging system in which a discontinuous lipophilic outer phase forms within a continuous lignophilic phase, it will be appreciated that the reverse relationship is also possible. Specifically, forming microcapsules containing a dye or chromogenic material that is more hydrophilic and first rendering the microcapsule walls relatively hydrophobic, if not impermeable, for entrapping the dye. If microcapsule wall formers are present, relatively hydrophilic binders similar to those described above can also be used. An important point to note is that a very wide range of imaging dyes and chromogenic materials can be used. Hartman, US Pat. No. 4,315,978, shows various yellow, magenta and cyan dyes containing polar substituents to provide additional mobility in hydrophilic media.

Although only a few of the various imaging systems that constitute the preferred embodiments of the present invention are specifically described, further imaging systems that utilize addition-curable organic components at sites of ethylenically unsaturation are also described. It is clear that improvements can be made by including a co-initiator.

〔Example〕

Examples will be shown below to explain the present invention more specifically, but it goes without saying that the present invention is not limited to these Examples.

The various dyes to be tested as photosensitizers were each 0.0
A series of imageable compositions containing 2 mmol were prepared.

The imaging composition was formulated as follows.

2.34 g Binder A1.17 g
Nanatsuma-B 1.17 g Monomer C 0,012 g! IJfill agent D0.21
g Enhancer E 0.077 g Activator F 2X10-' mol Photosensitizer 10.32 g Solvent (dichloromethane) Structure of binder A: Structure of monomer B: Structure of monomer C: Structure of inhibitor R: Enhancement Agent E: Ethyldimethylaminobenzoate Activator F: 1-Methoxy-4-phenylpyridinium tetrafluoroborate Each imageable composition was coated onto the sinus sheet using a 0.3 Dragon coating knife, approximately 70% It was dried at ℃ for 10 minutes. A clear polypropylene cover sheet was then placed over the coating.

Since the imageable composition without photosensitizer coinitiator is responsive to ultraviolet light exposure, shorter wavelengths were filtered out during exposure. In particular, wavelengths below the absorption peak of the photosensitizer can filter 99.9% of the radiation at wavelengths below 400.510 or 580ne+, respectively.
W-16 or H-25 Wratten filters were used to remove. Filtration of each coated sample was performed through a Kodak T-14 stethoscope 7) with 14 equivalent incremental concentration steps ranging from essentially zero to 2.1 concentration. A Nu-arc FT32 equipped with a 4000 watt pulsed xenon lamp was used for 3 minute exposures.
This was done using an L flip-top plate making machine. After exposure, bake the sample at 70°C for 10 minutes.
and spray developed.

Development was carried out using 1.1','1-trichloroethane as a developer. The response was measured in the number of stepped exposure areas (steps) in which the photoresist remained for the next exposure. For example, a photoresist sample that remained in the next exposure and development in 10 steps but not in the remaining 4 steps received a step rating of 10. If partial retention of the imageable composition was observed in the 11th step, this was indicated by a positive rating, ie 10+. On the other hand, if the photoresist residue was deemed to be barely worthy of a step rating, this was indicated by a negative rating, ie, IO-.

The results with various dye sensitizers are shown in Table 1 below. On each side, results are also shown for a pair of control imaging compositions, one lacking Enhancer E or one lacking Activator F.

I RR PS-1-3-1-CH2CH3'CffFtCOO-
1001l-PS-2-0-3-CII□C11, de
4 0 6゜PS-3C(Cth)z
2 CH3I-405PS 4 C11-CHOC
aHq ndo 204RR PS-5R=CIIs
9” 0 11PS-6R=C6H59
-10011 a) This coumarin derivative without either activator F or enhancer E gives two steps.

From Table 1, it is clear that in the examples, enhancer E did not function as an activator when used with only the photosensitizer as co-initiator. When Enhancer E was used in combination with Activator F, an increase in photosensitivity was observed on each side.

No imaging response was observed as a result of implementing the method described above, including filters used for exposure in the presence of dye, when the imageable composition was changed only by removing the dye sensitizer. This indicated that the activator was not effective for imparting sensitivity to the imaging composition in the visible region of the spectrum.

The wavelength of the main absorption peak of each dye photosensitizer listed in Table 1 is as follows.

PSl 560nm PS -2702nm PS 3 650nm PS 4 532nm PS 5 642nm PS 6 652nm PS -7447nm PS -8592nm Dye sensitizer PS-6 used in combination with activator F and modified enhancer and the method of Examples 1-8 was repeated.

The results are shown in Table ① above.

Below remainder α IL table R , to /°.

, 1. . 13) 2 R Nujko and Otomaru C00CJs 11COCH, 11 CHO11"-12- COC, H, 10'-11- CN 10"-11-No enhancer 9-10゜H9-10" *Control enhancer present When not, the results are consistent with those shown in Table 1 above. Also, no sensitivity enhancement is observed when the benzene ring is unsubstituted other than with an amino substituent. shows the importance of electron-withdrawing substituents on the benzene ring in order to obtain

〔Effect of the invention〕

In accordance with the present invention, the increased sensitivity curable imageable composition provides a true Hammett sigma electron withdrawing property of at least +0.20 volts as an azinium salt activator, photosensitizer, and enhancer. It has been quite surprisingly found that this is achieved when the resulting aniline substituted with one or more groups is used in combination with a co-initiator. In the comparative experiments shown in the examples above, it is shown that the enhancer is not effective in the absence of either the photosensitizer or the azinium salt activator. Furthermore, at visible exposure wavelengths, azinium salt activators are ineffective as initiators in the absence of photosensitizers. Additionally, photosensitizers are generally ineffective in the absence of an initiator. Thus, all three co-initiators were found to be essential to achieve the best possible curing response of the imageable compositions of the present invention.

The present invention consists of 1. In addition to the enhanced sensitivity of curable imageable compositions, they provide other highly desirable imaging properties. First, when dye photosensitizers are used, the curable imageable compositions can be used at blue, green, red, and near-infrared wavelengths as well as near-ultraviolet wavelengths of the more commonly used exposing radiation. have been found to be able to respond effectively to imaging radiation of Second, the curable imageable composition nevertheless exhibits thermal and storage stability comparable to that of curable imageable compositions that respond to shorter wavelength imaging exposures. By having the ability to respond to longer wavelength exposing radiation, the curable imageable composition is capable of forming an image forming plate that relies on differences in visible wavelength radiation transmission for image resolution, i.e., an image containing a visible image. Particularly suitable for forming blanks.

The use of dye photosensitizers itself particularly contributes to the formation of polychromatic images.

A particularly noteworthy feature of the curable imageable compositions of the present invention is that they have a primary absorption peak at wavelengths greater than 500 nm and are effective with dyes used as photosensitizers (hereinafter referred to as longer wavelength dyes). It is to form an image. Furthermore, if the dye reduction potential is appropriately related to that of the azinium salt activator with which it is used, the dye photosensitizer can react with both yellow dyes and longer wavelength dyes, regardless of dye type. You can choose from.

Another notable feature is that the dye photosensitizer was found to be effective despite exhibiting an intersystem cross-over efficiency to the triple state of less than 10%. To the limited extent that technology has previously reported photosensitizer co-initiators for azinium activators, consideration is given to photosensitizers that exhibit high (greater than 20%) intersystem cross-efficiency to the triple state. limited to.

This choice is based on the reason that dye photosensitizers with long lifetimes above the ground state have a better chance of transferring energy to the azinium-activated coinitiator.

Most of the known photosensitizer co-initiators exhibit significant radiation absorption that extends into the visible spectrum and therefore should be considered as dyes, especially amino-substituted ketocoumarins and ketomethylene (i.e. merocyanine) yellow keto dyes. There wasn't. All showed high intersystem cross-over efficiency to triplex states.

These photosensitizers were not longer wavelength dyes.

Now, dyes that include longer wavelength dyes and satisfy the reduction potential specified in relation to the azinium activator used together, regardless of the dye type selected, can be used in a higher or lower triple state. It has been observed that photosensitizers are commonly used as co-initiators, regardless of their intersystem cross-efficiency. The above i136 opens up a wider selection of dyes than previously thought to be useful as photosensitizers with azinium activators for curing by initiation of ethylenic addition reactions.

Margin below

Claims (1)

[Scope of Claims] 1. An organic component containing an ethylenically unsaturated site and capable of being selectively cured by addition at the ethylenically unsaturated site, an azinium salt activator, and a reduction potential of the azinium salt activator. a photosensitizer with a reduction potential that is up to 0.1 volt more positive with respect to the electron-donating amino group and the benzene ring at least +0.1 volt.
An imageable composition comprising an image-enhancing amount of benzene substituted with one or more groups capable of providing a true Hammett sigma electron withdrawing property of 2 volts.